"""
django-helpdesk - A Django powered ticket tracker for small enterprise.

(c) Copyright 2008 Jutda. All Rights Reserved. See LICENSE for details.

forms.py - Definitions of newforms-based forms for creating and maintaining
           tickets.
"""
from django.core.exceptions import ObjectDoesNotExist

try:
    from StringIO import StringIO
except ImportError:
    from io import StringIO

from django import forms
from django.forms import extras
from django.conf import settings
from django.utils.translation import ugettext_lazy as _
from django.contrib.auth import get_user_model
try:
    from django.utils import timezone
except ImportError:
    from datetime import datetime as timezone

from helpdesk.lib import send_templated_mail, safe_template_context
from helpdesk.models import (Ticket, Queue, FollowUp, Attachment, IgnoreEmail, TicketCC,
                             CustomField, TicketCustomFieldValue, TicketDependency)
from helpdesk import settings as helpdesk_settings

User = get_user_model()


class CustomFieldMixin(object):
    """
    Mixin that provides a method to turn CustomFields into an actual field
    """

    def customfield_to_field(self, field, instanceargs):
        if field.data_type == 'varchar':
            fieldclass = forms.CharField
            instanceargs['max_length'] = field.max_length
        elif field.data_type == 'text':
            fieldclass = forms.CharField
            instanceargs['widget'] = forms.Textarea
            instanceargs['max_length'] = field.max_length
        elif field.data_type == 'integer':
            fieldclass = forms.IntegerField
        elif field.data_type == 'decimal':
            fieldclass = forms.DecimalField
            instanceargs['decimal_places'] = field.decimal_places
            instanceargs['max_digits'] = field.max_length
        elif field.data_type == 'list':
            fieldclass = forms.ChoiceField
            choices = field.choices_as_array
            if field.empty_selection_list:
                choices.insert(0, ('', '---------'))
            instanceargs['choices'] = choices
        elif field.data_type == 'boolean':
            fieldclass = forms.BooleanField
        elif field.data_type == 'date':
            fieldclass = forms.DateField
        elif field.data_type == 'time':
            fieldclass = forms.TimeField
        elif field.data_type == 'datetime':
            fieldclass = forms.DateTimeField
        elif field.data_type == 'email':
            fieldclass = forms.EmailField
        elif field.data_type == 'url':
            fieldclass = forms.URLField
        elif field.data_type == 'ipaddress':
            fieldclass = forms.IPAddressField
        elif field.data_type == 'slug':
            fieldclass = forms.SlugField

        self.fields['custom_%s' % field.name] = fieldclass(**instanceargs)


class EditTicketForm(CustomFieldMixin, forms.ModelForm):

    class Meta:
        model = Ticket
        exclude = ('created', 'modified', 'status', 'on_hold', 'resolution', 'last_escalation', 'assigned_to')

    def __init__(self, *args, **kwargs):
        """
        Add any custom fields that are defined to the form
        """
        super(EditTicketForm, self).__init__(*args, **kwargs)

        for field in CustomField.objects.all():
            try:
                current_value = TicketCustomFieldValue.objects.get(ticket=self.instance, field=field)
                initial_value = current_value.value
            except TicketCustomFieldValue.DoesNotExist:
                initial_value = None
            instanceargs = {
                'label': field.label,
                'help_text': field.help_text,
                'required': field.required,
                'initial': initial_value,
            }

            self.customfield_to_field(field, instanceargs)

    def save(self, *args, **kwargs):

        for field, value in self.cleaned_data.items():
            if field.startswith('custom_'):
                field_name = field.replace('custom_', '', 1)
                customfield = CustomField.objects.get(name=field_name)
                try:
                    cfv = TicketCustomFieldValue.objects.get(ticket=self.instance, field=customfield)
                except ObjectDoesNotExist:
                    cfv = TicketCustomFieldValue(ticket=self.instance, field=customfield)
                cfv.value = value
                cfv.save()

        return super(EditTicketForm, self).save(*args, **kwargs)


class EditFollowUpForm(forms.ModelForm):

    class Meta:
        model = FollowUp
        exclude = ('date', 'user',)

    def __init__(self, *args, **kwargs):
        """Filter not openned tickets here."""
        super(EditFollowUpForm, self).__init__(*args, **kwargs)
        self.fields["ticket"].queryset = Ticket.objects.filter(status__in=(Ticket.OPEN_STATUS, Ticket.REOPENED_STATUS))


class TicketForm(CustomFieldMixin, forms.Form):
    queue = forms.ChoiceField(
        label=_('Queue'),
        required=True,
        choices=()
    )

    title = forms.CharField(
        max_length=100,
        required=True,
        widget=forms.TextInput(attrs={'size': '60'}),
        label=_('Summary of the problem'),
    )

    submitter_email = forms.EmailField(
        required=False,
        label=_('Submitter E-Mail Address'),
        widget=forms.TextInput(attrs={'size': '60'}),
        help_text=_('This e-mail address will receive copies of all public '
                    'updates to this ticket.'),
    )

    body = forms.CharField(
        widget=forms.Textarea(attrs={'cols': 47, 'rows': 15}),
        label=_('Description of Issue'),
        required=True,
    )

    assigned_to = forms.ChoiceField(
        choices=(),
        required=False,
        label=_('Case owner'),
        help_text=_('If you select an owner other than yourself, they\'ll be '
                    'e-mailed details of this ticket immediately.'),
    )

    priority = forms.ChoiceField(
        choices=Ticket.PRIORITY_CHOICES,
        required=False,
        initial='3',
        label=_('Priority'),
        help_text=_('Please select a priority carefully. If unsure, leave it as \'3\'.'),
    )

    due_date = forms.DateTimeField(
        widget=extras.SelectDateWidget,
        required=False,
        label=_('Due on'),
    )

    def clean_due_date(self):
        data = self.cleaned_data['due_date']
        # TODO: add Google calendar update hook
        # if not hasattr(self, 'instance') or self.instance.due_date != new_data:
        #     print "you changed!"
        return data

    attachment = forms.FileField(
        required=False,
        label=_('Attach File'),
        help_text=_('You can attach a file such as a document or screenshot to this ticket.'),
    )

    def __init__(self, *args, **kwargs):
        """
        Add any custom fields that are defined to the form
        """
        super(TicketForm, self).__init__(*args, **kwargs)
        for field in CustomField.objects.all():
            instanceargs = {
                'label': field.label,
                'help_text': field.help_text,
                'required': field.required,
            }

            self.customfield_to_field(field, instanceargs)

    def save(self, user):
        """
        Writes and returns a Ticket() object
        """

        q = Queue.objects.get(id=int(self.cleaned_data['queue']))

        t = Ticket(title=self.cleaned_data['title'],
                   submitter_email=self.cleaned_data['submitter_email'],
                   created=timezone.now(),
                   status=Ticket.OPEN_STATUS,
                   queue=q,
                   description=self.cleaned_data['body'],
                   priority=self.cleaned_data['priority'],
                   due_date=self.cleaned_data['due_date'],
                   )

        if self.cleaned_data['assigned_to']:
            try:
                u = User.objects.get(id=self.cleaned_data['assigned_to'])
                t.assigned_to = u
            except User.DoesNotExist:
                t.assigned_to = None
        t.save()

        for field, value in self.cleaned_data.items():
            if field.startswith('custom_'):
                field_name = field.replace('custom_', '', 1)
                customfield = CustomField.objects.get(name=field_name)
                cfv = TicketCustomFieldValue(ticket=t,
                                             field=customfield,
                                             value=value)
                cfv.save()

        f = FollowUp(ticket=t,
                     title=_('Ticket Opened'),
                     date=timezone.now(),
                     public=True,
                     comment=self.cleaned_data['body'],
                     user=user,
                     )
        if self.cleaned_data['assigned_to']:
            f.title = _('Ticket Opened & Assigned to %(name)s') % {
                'name': t.get_assigned_to
            }

        f.save()

        files = []
        if self.cleaned_data['attachment']:
            import mimetypes
            file = self.cleaned_data['attachment']
            filename = file.name.replace(' ', '_')
            a = Attachment(
                followup=f,
                filename=filename,
                mime_type=mimetypes.guess_type(filename)[0] or 'application/octet-stream',
                size=file.size,
            )
            a.file.save(file.name, file, save=False)
            a.save()

            if file.size < getattr(settings, 'MAX_EMAIL_ATTACHMENT_SIZE', 512000):
                # Only files smaller than 512kb (or as defined in
                # settings.MAX_EMAIL_ATTACHMENT_SIZE) are sent via email.
                try:
                    files.append([a.filename, a.file])
                except NotImplementedError:
                    pass

        context = safe_template_context(t)
        context['comment'] = f.comment

        messages_sent_to = []

        if t.submitter_email:
            send_templated_mail(
                'newticket_submitter',
                context,
                recipients=t.submitter_email,
                sender=q.from_address,
                fail_silently=True,
                files=files,
            )
            messages_sent_to.append(t.submitter_email)

        if t.assigned_to and \
                t.assigned_to != user and \
                t.assigned_to.usersettings.settings.get('email_on_ticket_assign', False) and \
                t.assigned_to.email and \
                t.assigned_to.email not in messages_sent_to:
            send_templated_mail(
                'assigned_owner',
                context,
                recipients=t.assigned_to.email,
                sender=q.from_address,
                fail_silently=True,
                files=files,
            )
            messages_sent_to.append(t.assigned_to.email)

        if q.new_ticket_cc and q.new_ticket_cc not in messages_sent_to:
            send_templated_mail(
                'newticket_cc',
                context,
                recipients=q.new_ticket_cc,
                sender=q.from_address,
                fail_silently=True,
                files=files,
            )
            messages_sent_to.append(q.new_ticket_cc)

        if q.updated_ticket_cc and \
                q.updated_ticket_cc != q.new_ticket_cc and \
                q.updated_ticket_cc not in messages_sent_to:
            send_templated_mail(
                'newticket_cc',
                context,
                recipients=q.updated_ticket_cc,
                sender=q.from_address,
                fail_silently=True,
                files=files,
            )

        return t


class PublicTicketForm(CustomFieldMixin, forms.Form):
    queue = forms.ChoiceField(
        label=_('Queue'),
        required=True,
        choices=()
    )

    title = forms.CharField(
        max_length=100,
        required=True,
        widget=forms.TextInput(),
        label=_('Summary of your query'),
    )

    submitter_email = forms.EmailField(
        required=True,
        label=_('Your E-Mail Address'),
        help_text=_('We will e-mail you when your ticket is updated.'),
    )

    body = forms.CharField(
        widget=forms.Textarea(),
        label=_('Description of your issue'),
        required=True,
        help_text=_('Please be as descriptive as possible, including any '
                    'details we may need to address your query.'),
    )

    priority = forms.ChoiceField(
        choices=Ticket.PRIORITY_CHOICES,
        required=True,
        initial='3',
        label=_('Urgency'),
        help_text=_('Please select a priority carefully.'),
    )

    due_date = forms.DateTimeField(
        widget=extras.SelectDateWidget,
        required=False,
        label=_('Due on'),
    )

    attachment = forms.FileField(
        required=False,
        label=_('Attach File'),
        help_text=_('You can attach a file such as a document or screenshot to this ticket.'),
        max_length=1000,
    )

    def __init__(self, *args, **kwargs):
        """
        Add any custom fields that are defined to the form
        """
        super(PublicTicketForm, self).__init__(*args, **kwargs)
        for field in CustomField.objects.filter(staff_only=False):
            instanceargs = {
                'label': field.label,
                'help_text': field.help_text,
                'required': field.required,
            }

            self.customfield_to_field(field, instanceargs)

    def save(self):
        """
        Writes and returns a Ticket() object
        """

        q = Queue.objects.get(id=int(self.cleaned_data['queue']))

        t = Ticket(
            title=self.cleaned_data['title'],
            submitter_email=self.cleaned_data['submitter_email'],
            created=timezone.now(),
            status=Ticket.OPEN_STATUS,
            queue=q,
            description=self.cleaned_data['body'],
            priority=self.cleaned_data['priority'],
            due_date=self.cleaned_data['due_date'],
        )

        if q.default_owner and not t.assigned_to:
            t.assigned_to = q.default_owner

        t.save()

        for field, value in self.cleaned_data.items():
            if field.startswith('custom_'):
                field_name = field.replace('custom_', '', 1)
                customfield = CustomField.objects.get(name=field_name)
                cfv = TicketCustomFieldValue(ticket=t,
                                             field=customfield,
                                             value=value)
                cfv.save()

        f = FollowUp(
            ticket=t,
            title=_('Ticket Opened Via Web'),
            date=timezone.now(),
            public=True,
            comment=self.cleaned_data['body'],
        )

        f.save()

        files = []
        if self.cleaned_data['attachment']:
            import mimetypes
            file = self.cleaned_data['attachment']
            filename = file.name.replace(' ', '_')
            a = Attachment(
                followup=f,
                filename=filename,
                mime_type=mimetypes.guess_type(filename)[0] or 'application/octet-stream',
                size=file.size,
            )
            a.file.save(file.name, file, save=False)
            a.save()

            if file.size < getattr(settings, 'MAX_EMAIL_ATTACHMENT_SIZE', 512000):
                # Only files smaller than 512kb (or as defined in
                # settings.MAX_EMAIL_ATTACHMENT_SIZE) are sent via email.
                files.append([a.filename, a.file])

        context = safe_template_context(t)

        messages_sent_to = []

        send_templated_mail(
            'newticket_submitter',
            context,
            recipients=t.submitter_email,
            sender=q.from_address,
            fail_silently=True,
            files=files,
        )
        messages_sent_to.append(t.submitter_email)

        if t.assigned_to and \
                t.assigned_to.usersettings.settings.get('email_on_ticket_assign', False) and \
                t.assigned_to.email and \
                t.assigned_to.email not in messages_sent_to:
            send_templated_mail(
                'assigned_owner',
                context,
                recipients=t.assigned_to.email,
                sender=q.from_address,
                fail_silently=True,
                files=files,
            )
            messages_sent_to.append(t.assigned_to.email)

        if q.new_ticket_cc and q.new_ticket_cc not in messages_sent_to:
            send_templated_mail(
                'newticket_cc',
                context,
                recipients=q.new_ticket_cc,
                sender=q.from_address,
                fail_silently=True,
                files=files,
            )
            messages_sent_to.append(q.new_ticket_cc)

        if q.updated_ticket_cc and \
                q.updated_ticket_cc != q.new_ticket_cc and \
                q.updated_ticket_cc not in messages_sent_to:
            send_templated_mail(
                'newticket_cc',
                context,
                recipients=q.updated_ticket_cc,
                sender=q.from_address,
                fail_silently=True,
                files=files,
            )

        return t


class UserSettingsForm(forms.Form):
    login_view_ticketlist = forms.BooleanField(
        label=_('Show Ticket List on Login?'),
        help_text=_('Display the ticket list upon login? Otherwise, the dashboard is shown.'),
        required=False,
    )

    email_on_ticket_change = forms.BooleanField(
        label=_('E-mail me on ticket change?'),
        help_text=_('If you\'re the ticket owner and the ticket is changed via the web by somebody else, do you want to receive an e-mail?'),
        required=False,
    )

    email_on_ticket_assign = forms.BooleanField(
        label=_('E-mail me when assigned a ticket?'),
        help_text=_('If you are assigned a ticket via the web, do you want to receive an e-mail?'),
        required=False,
    )

    email_on_ticket_apichange = forms.BooleanField(
        label=_('E-mail me when a ticket is changed via the API?'),
        help_text=_('If a ticket is altered by the API, do you want to receive an e-mail?'),
        required=False,
    )

    tickets_per_page = forms.IntegerField(
        label=_('Number of tickets to show per page'),
        help_text=_('How many tickets do you want to see on the Ticket List page?'),
        required=False,
        min_value=1,
        max_value=1000,
    )

    use_email_as_submitter = forms.BooleanField(
        label=_('Use my e-mail address when submitting tickets?'),
        help_text=_('When you submit a ticket, do you want to automatically use your e-mail address as the submitter address? You can type a different e-mail address when entering the ticket if needed, this option only changes the default.'),
        required=False,
    )


class EmailIgnoreForm(forms.ModelForm):

    class Meta:
        model = IgnoreEmail
        exclude = []


class TicketCCForm(forms.ModelForm):

    class Meta:
        model = TicketCC
        exclude = ('ticket',)

    def __init__(self, *args, **kwargs):
        super(TicketCCForm, self).__init__(*args, **kwargs)
        if helpdesk_settings.HELPDESK_STAFF_ONLY_TICKET_CC:
            users = User.objects.filter(is_active=True, is_staff=True).order_by(User.USERNAME_FIELD)
        else:
            users = User.objects.filter(is_active=True).order_by(User.USERNAME_FIELD)
        self.fields['user'].queryset = users


class TicketDependencyForm(forms.ModelForm):

    class Meta:
        model = TicketDependency
        exclude = ('ticket',)